Brush-gear for dynamo-electric machines.



J. C. TODMAN, T. L. R. COOPER & A. A. LYON.

BRUSH GEAR FOR DYNAMO ELECTRIC MACHINES.

APPLICATION FILED OCT-15. I918.

I/VY ENTURS Patented Apr. 1, 1919.

UNITED STATES PATENT OFFICE.

JAMES CLAUD TODD/IAN, 0L ACTON, THOMAS LANCELOT REED COOPER, OF EALIN G, AND ARTHUR ANDERSON LYON, OF HARROW, LONDON, ENGLAND.

BRUSH-GEAR FOR DYNAMIC-ELECTRIC MACHINES.

To all whom it may concern:

Be it known that we, JAMES CLAUD TODMAN, of 29 Goldsmith avenue, Acton, THOMAS LANOELOT REED Coornn, 10 Gordon road, Ealing, and ARTHUR ANDERSON LYON, of 12 Sheepcote road, Harrow, in the city of London, England, engineers, have invented a certain new and useful Brush-Gear for Dynamo-Electric Machines, of which the following is a specification.

'This invention relates to an improved brush gear for electric dynamos and motors.

The object of the invention is to provide an arrangement of brush gear which can be more easily applied to and removed from either the end bracket or the commutator end frame of a dynamo-electric machine, relatively to the arrangements heretofore employed.

In the arrangement according to this invention the brush carrier is secured in position by means arranged outside the end bracket of the machine permitting the brush carrier to be readily applied to and removed from the machine entirely in a direction parallel to the shaft of the'machine,that is, without any necessity for the attendant to handle any part located between the outer end of the commutator and the opposite end of the machine. A secondary feature of the invention comprises an arrangement for facilitating the adjustment of the brush tension mechanism regulating the pressure of the brushes upon the commutator, and also for adjusting the positions of the various brushes in the direction of the axis of the commutator.

By way of example, one form of the invention is illustrated by the accompanying drawings wherein Figure 1 is a part sectional side elevation, Fig. 2 is a plan of the brush-holder with its support and cable clipping device. Fig. 3 shows a portion of the end bracket and rocker ring and one brush-holder. Fig. l is a sectional view illustratin the clamping plate.

Referring to the drawings, a brush holder of the box form 1 has a spindle or support 2 on which is mounted a bridge piece 8, the support being substantially parallel to the shaft of the machine and each brush-holder being attached to a ring lby means of an insulating bush 5 held against the support by the plate 6 and screws 7 or alternatively by a screw spindle provided with suitable nuts Specification of Letters Patent.

Patented Apr. 1, 1919.

Application filed October 15, 1918. Serial No. 258,256.

or otherwise adapted to form a terminal. Pivoted against the sides of the bridge piece 3 is a lever 8 one end of which is provided with a pin 9 immediately over the center of the brush 10. This pin supports a spring v11 with two curved arms, one of which bears upon each side of the top of the brush. From the fork of the lever 8 an arm 12 depends in a direction sloping toward and be low the fulcrum making the effective form of the lever substantially that of a bell crank. One end of the tension spring 13 is attached to this arm, the spring passing be tween the arms of the fork and within the central space in the bridge piece. The far end of the spring is attached to a threaded pin 1 which passes through a hole in a suitable support 15 which may be formed as shown or may be separate. and held against the outer side of the insulating bush by means of a nut. A milled nut 16 or the like is employedupon the above mentioned threaded pin toadjust the tension of the spring.

The relative positions of the points of attachment of the spring and pivot of the bell crank lever are so arranged that when the arm is raised from the brush through a suitable angle, it is locked in this position enabling the brush to be easily removed.

As many brush holders as may be required may be attached as mentioned above to a brush ring 4 from which they are insulated by the insulating bushes. The brush ring is arranged to rock against the front of the end bracket 18. In one form it is secured by means of plates 19 each having one end held by a pin 20 or similarly upon one of the arms of the end bracket and its opposite end bearing against the outer surface of the brush ring. A screw 21 is arranged to pass through the central portion of the plate so that by tightening up the screw the brush ring is tightly gripped, while it may be rocked when the screws are loosened, and by removing the screws and turning the plates about the pins, the brush ring is released and the whole brush gear may be removable bodily with it, when desired.

In the form illustrated, the brush holder support 2 is split horizontally at its outer end forming two holes 22 and 23 within which the cable sockets may be gripped by means of the screw 24:. A smaller hole is drilled in the inner extremity of the slot in order to cause this gripping device to be sufliciently elastic.

It Will be seen at once from Figs. 1 and 3 that spaces in the end bracket enable the brushholders to be drawn out bodily through the bracket With the ring when the latter is removed.

Other equivalent arrangements of the brushholder may be employed and the brushholders may be employed in different Ways. The above detailed description being given by Way of example to make clear the nature of the invention.

Claims:

1. Brush gear for a dynamo-electric machine, comprising a rocker ring, brushholders of the box type mounted thereon and arranged on One side of and perpendicular to the ring, tension mechanism acting uponthe brushes in planes passing through the center of the ring, means for adjusting the tension mechanism accessible from the other side of the ring, and means for securing the ring to the outside of the end bearing bracket of the machine, the Whole so arranged that the ring and parts mounted thereon may be removed laterally in the direction of the axis of the ring.

2. Brush gear for a dynamo-electric machine comprising a rocker ring, brushholders of the box type mounted thereon and arranged on one side of and perpendicular to the ring, tension mechanism acting upon the brushes in planes passing through the center of the ring, means arranged'upon the other side ofthe ring'for' adjusting the said mechanism, and means enabling the ring and attached parts to be adjustably secured to and removed from the outside of the end bearing bracket of the machine.

A brush gear for electrical machines comprising a spindle extending axially of the machine and adjustable longitudinally thereon, a bracket formed at one end, of the spindle, a brush in said bracket, and tension mechanism arranged longitudinally of the spindle for adjusting the pressure of the brush upon the commutator.-

4. In a dynamo-electric machine, a commutator comprising segmental bars arranged with their longitudinal axesv parallel to the axis of the machine, an end frame,-brushes bearing upon the periphery of the commutator, a rocker ring, brush holders mounted on the rocker'ring, means for clamping the rocker ring" to the end frame, and means car riedby the brush holders for adjusting the pressure of the brushes upon the commutator. I

In testimony whereof We have signed our names to this specification. JAMES OLAUDTODMAN; THOMAS LANCELOT REED COOPER.- ARTHUR ANDERSON LYON.

Copies of this patent may be obtained for five cents eaclnby addressingtthe' Commissioner of Patents,

Washington, I). O. i 

